1．If you want to do the experiment again，you'd better be more careful ________ you made a mistake.
A．when B．why C．where D．that
【答案】C 【解析】你最好在你犯过错的“地方”更小心点，故选where，where引导状语从句。
2．Jessica was a newcomer to our class，but，________ we didn't know her，she was warmly received.
A．as B．since C．for D．although
【答案】D 【解析】although引导让步状语从句。
3.—How long do you suppose it is ________ he left for Japan?
—No more than half a month.
A．that B．before C．after D．since
【答案】D 【解析】此为since引导的时间状语从句。句意：你觉得自从他去日本以来有多长时间了？
4．________ I can see，there's only one possible way from the danger.
A．As long as B．As far as
C．As soon as D．Even if
【答案】B 【解析】as far as I can see是固定说法，意为：据我所知。
